An ancient dog breed regulates pitch when howling with music

Singing occurs in every human society, most commonly as group singing where individuals coordinate their vocal pitches¹. Coordinating pitch with other simultaneous voices is not necessary for ordinary speech, which involves turn taking, yet this ability can develop without formal training and is a widespread component of human musicality². Did our ability to coordinate pitch in a group emerge as a byproduct of complex vocal learning or earlier because of its adaptive value? The latter possibility aligns with current theories of music origins, which posit that pitch-coordinated group vocalizations served to signal group strength and size or strengthen social bonds^3,4, implying the ability might exist in mammals without complex vocal learning. Wolves, for example, lack complex vocal learning but are suggested to 'detune' their howls during territorial pack displays to exaggerate group size⁵. Simultaneous pitch regulation could also serve prosocial functions of howling like pack reunion⁵, for example via convergence of vocal pitches. Thus we hypothesized that ancient breed dogs, which share more genetic similarity to wolves than do modern breeds⁶, would change vocal pitch when howling with frequency-shifted sounds. Utilizing the tendency of some dogs to howl along with music, we found that Samoyeds significantly changed mean vocal pitch when howling with music that had been shifted up versus down in frequency. This shows that simultaneous pitch regulation can evolve independently of complex vocal learning in group-vocalizing mammals and might predate the evolution of complex vocal learning in our ancestors.